package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.search.config.GulimallElasticSearchConfig;
import com.atguigu.gulimall.search.constant.EsConstant;
import com.atguigu.gulimall.search.feign.ProductFeignService;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.AttrResponseVo;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import lombok.extern.slf4j.Slf4j;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.*;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import javax.annotation.Resource;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author phil
 * @create 2022-01-06 14:16
 */
@Slf4j
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;
    @Resource
    private ProductFeignService productFeignService;
    /**
     * @param param 检索的所有参数
     * @return 返回检索的结果
     */
    @Override
    public SearchResult search(SearchParam param) {
        //1、动态构建出查询需要的 DSL 语句
        SearchResult result = null;
        //1、准备检索请求
        SearchRequest searchRequest = buildSearchRequest(param);

        try {
            //2、执行检索请求
            SearchResponse response = client.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);
            //3、分析响应数据封装
            result = buildSearchResult(response, param);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 准备检索请求
     * 模糊匹配，过滤（按照，分类，品牌，价格区间，库存，属性），排序，分页，高亮，聚合分析
     *
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        /**
         * 1.模糊匹配，过滤（按照，分类，品牌，价格区间，库存，属性）
         */
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        //1.0 模糊匹配
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }
        //1.1 bool -> filter 过滤 按照分类 catalogId
        if (param.getCatalog3Id() != null) {
            boolQuery.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }
        //1.2 bool -> filter 过滤 按照品牌 brandId
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            boolQuery.filter(QueryBuilders.termsQuery("brandId", param.getBrandId()));
        }
        //1.3 bool -> filter 过滤 按照库存 hasStock
        if(param.getHasStock() != null){
            boolQuery.filter(QueryBuilders.termQuery("hasStock", param.getHasStock() == 1));
        }
        //1.4 bool -> filter 过滤 按照价格区间 skuPrice 。。。。。。
        if (!StringUtils.isEmpty(param.getSkuPrice())) {
            //1_500/_500/500_
            String[] s = param.getSkuPrice().split("_");
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            if (s.length == 2) {
                rangeQuery.gte(s[0]);
                rangeQuery.lte(s[1]);
            } else if (s.length == 1) {
                if (param.getSkuPrice().startsWith("_")) {
                    rangeQuery.lte(s[0]);
                } else if (param.getSkuPrice().endsWith("_")) {
                    rangeQuery.gte(s[0]);
                }
            }
            boolQuery.filter(rangeQuery);
        }
        //1.4 bool -> filter 过滤 按照属性 attrs
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            for (String attrStr : param.getAttrs()) {
                BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
                //attrs=1_5寸:8寸&attrs=2_16G:8G
                String[] s = attrStr.split("_");
                String attrId = s[0];//检索属性id
                String[] attrValues = s[1].split(":");//检索属性值
                boolQueryBuilder.must(QueryBuilders.termQuery("attrs.attrId", attrId));
                boolQueryBuilder.must(QueryBuilders.termsQuery("attrs.attrValue", attrValues));

                //每个属性必须生成一个nested查询
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", boolQueryBuilder, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }
        }

        //综合以上所有查询，构建查询条件
        sourceBuilder.query(boolQuery);

        /**
         * 2.排序，分页，高亮
         */
        //2.1 排序
        if (!StringUtils.isEmpty(param.getSort())) {
            //sort=hotScore_asc/desc
            String[] s = param.getSort().split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }
        //2.2 分页
        //pageNum: 1 from:0 size:5  [0,1,2,3,4]
        //pageNum: 2 from:5 size:5
        //from = (pageNum - 1)*size
        sourceBuilder.from((param.getPageNum() - 1) * EsConstant.PRODUCT_PAGESIZE);
        sourceBuilder.size(EsConstant.PRODUCT_PAGESIZE);

        //2.3 高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder highlightBuilder = new HighlightBuilder();
            highlightBuilder.field("skuTitle");
            highlightBuilder.preTags("<b style='color:red'>");
            highlightBuilder.postTags("</b>");

            sourceBuilder.highlighter(highlightBuilder);
        }

        /**
         * 聚合分析
         */
        //TODO:  1. 品牌聚合 brand_agg
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        //1.1 品牌名字子聚合 brand_name_agg
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        //1.2 品牌图片子聚合 brand_img_agg
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        sourceBuilder.aggregation(brand_agg);

        //TODO:  2. 分类聚合 catalog_agg
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(50);
        //2.1 分类名字子聚合 catalog_name
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        sourceBuilder.aggregation(catalog_agg);

        // TODO: 3. 属性聚合 attr_agg
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        //3.1 属性 id 聚合
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        attr_agg.subAggregation(attr_id_agg);
        //3.2 属性名字 聚合 attr_name_agg
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        //3.2 属性值 聚合 attr_value_agg
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        sourceBuilder.aggregation(attr_agg);



        System.out.println("构建的DSL语句：" + sourceBuilder.toString());

        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, sourceBuilder);
        return searchRequest;
    }

    /**
     * 封装响应数据
     *
     * @param response
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse response, SearchParam param) {
        SearchResult result = new SearchResult();

        SearchHits hits = response.getHits();

        //1. 返回所有查询到的商品
        List<SkuEsModel> esModels = new ArrayList<>();
        if (hits.getHits() != null && hits.getHits().length > 0) {
            for (SearchHit hit : hits.getHits()) {
                String sourceAsString = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);
                //设置高亮
                if(!StringUtils.isEmpty(param.getKeyword())){
                    String skuTitle = hit.getHighlightFields().get("skuTitle").getFragments()[0].string();
                    esModel.setSkuTitle(skuTitle);
                }
                esModels.add(esModel);
            }
        }
        result.setProduct(esModels);

//        //2. 当前所有商品涉及到的所有属性信息
        ParsedNested attr_agg = response.getAggregations().get("attr_agg");
        List<SearchResult.AttrVo> attrs = new ArrayList<>();
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            //属性id
            String attrId = bucket.getKeyAsString();
            attrVo.setAttrId(Long.parseLong(attrId));
            //属性名字
            ParsedStringTerms attr_name_agg =  bucket.getAggregations().get("attr_name_agg");
            String attrName = attr_name_agg.getBuckets().get(0).getKeyAsString();
            attrVo.setAttrName(attrName);
            //属性值
            ParsedStringTerms attr_value_agg = bucket.getAggregations().get("attr_value_agg");
            List<String> attrValues = new ArrayList<>();
            for (Terms.Bucket attr_value_aggBucket : attr_value_agg.getBuckets()) {
                String attrValue = attr_value_aggBucket.getKeyAsString();
                attrValues.add(attrValue);
            }
            attrVo.setAttrValue(attrValues);

            attrs.add(attrVo);
        }

        result.setAttrs(attrs);

//        //3. 当前所有商品涉及到的所有品牌信息
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        List<? extends Terms.Bucket> brand_aggBuckets = brand_agg.getBuckets();
        for (Terms.Bucket brand_aggBucket : brand_aggBuckets) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            //1.设置品牌id
            String brandId = brand_aggBucket.getKeyAsString();
            brandVo.setBrandId(Long.parseLong(brandId));
            //2.设置品牌图片
            ParsedStringTerms brand_img_agg = brand_aggBucket.getAggregations().get("brand_img_agg");
            String brandImg = brand_img_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandImg(brandImg);
            //3.设置品牌名字
            ParsedStringTerms brand_name_agg = brand_aggBucket.getAggregations().get("brand_name_agg");
            String brandName = brand_name_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandName(brandName);

            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);
//        //4. 当前所有商品涉及到的所有分类信息
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        List<? extends Terms.Bucket> catalog_aggBuckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : catalog_aggBuckets) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            //得到分类id
            String catalogId = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(catalogId));
            //得到分类名字
            ParsedStringTerms bucketAggregations = bucket.getAggregations().get("catalog_name_agg");
            String catalogName = bucketAggregations.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalogName);
            catalogVos.add(catalogVo);
        }
        result.setCatalogs(catalogVos);


//        //======================以上从聚合信息中获取====================
//        //5. 分页信息-页码
        result.setPageNum(param.getPageNum());
//        //5. 分页信息-总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);
//        //5. 分页信息-总页码
        int totalPage = (int) (total % EsConstant.PRODUCT_PAGESIZE == 0 ? (int) total / EsConstant.PRODUCT_PAGESIZE : (int) (total / EsConstant.PRODUCT_PAGESIZE + 1));
        result.setTotalPages(totalPage);
        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 1; i <= totalPage; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);

        //6、构建面包屑导航
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            List<SearchResult.NavVo> collect = param.getAttrs().stream().map(attr -> {
                //1、分析每一个attrs传过来的参数值
                SearchResult.NavVo navVo = new SearchResult.NavVo();
                //attrs=2_5寸：6寸
                String[] s = attr.split("_");
                navVo.setNavValue(s[1]);
                R r = productFeignService.attrInfo(Long.parseLong(s[0]));
//                添加选择的属性，方便前端去除
                result.getAttrIds().add(Long.parseLong(s[0]));

                if (r.getCode() == 0) {
                    AttrResponseVo data = r.getData("attr", new TypeReference<AttrResponseVo>() {});
                    navVo.setNavName(data.getAttrName());
                } else {
                    navVo.setNavName(s[0]);
                }

                //2、取消了这个面包屑以后，我们要跳转到哪个地方，将请求的地址url里面的当前置空
                //拿到所有的查询条件，去掉当前
                String encode = null;
                try {
                    encode = URLEncoder.encode(attr,"UTF-8");
                    encode = encode.replace("+","%20");  //浏览器对空格的编码和Java不一样，差异化处理
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                String replace = param.get_queryString().replace("&attrs=" + encode, "");
                navVo.setLink("http://search.gulimall.com/list.html?" + replace);

                return navVo;
            }).collect(Collectors.toList());

            result.setNavs(collect);
        }

        return result;
    }

}
